src/mesa/main/context.c

   1 /**
   2  * \file context.c
   3  * Mesa context/visual/framebuffer management functions.
   4  * \author Brian Paul
   5  */
   6
   7 /*
   8  * Mesa 3-D graphics library
   9  * Version:  7.1
  10  *
  11  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
  12  *
  13  * Permission is hereby granted, free of charge, to any person obtaining a
  14  * copy of this software and associated documentation files (the "Software"),
  15  * to deal in the Software without restriction, including without limitation
  16  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  17  * and/or sell copies of the Software, and to permit persons to whom the
  18  * Software is furnished to do so, subject to the following conditions:
  19  *
  20  * The above copyright notice and this permission notice shall be included
  21  * in all copies or substantial portions of the Software.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  24  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  25  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  26  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  27  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  28  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29  */
  30
  31
  32 /**
  33  * \mainpage Mesa Main Module
  34  *
  35  * \section MainIntroduction Introduction
  36  *
  37  * The Mesa Main module consists of all the files in the main/ directory.
  38  * Among the features of this module are:
  39  * <UL>
  40  * <LI> Structures to represent most GL state </LI>
  41  * <LI> State set/get functions </LI>
  42  * <LI> Display lists </LI>
  43  * <LI> Texture unit, object and image handling </LI>
  44  * <LI> Matrix and attribute stacks </LI>
  45  * </UL>
  46  *
  47  * Other modules are responsible for API dispatch, vertex transformation,
  48  * point/line/triangle setup, rasterization, vertex array caching,
  49  * vertex/fragment programs/shaders, etc.
  50  *
  51  *
  52  * \section AboutDoxygen About Doxygen
  53  *
  54  * If you're viewing this information as Doxygen-generated HTML you'll
  55  * see the documentation index at the top of this page.
  56  *
  57  * The first line lists the Mesa source code modules.
  58  * The second line lists the indexes available for viewing the documentation
  59  * for each module.
  60  *
  61  * Selecting the <b>Main page</b> link will display a summary of the module
  62  * (this page).
  63  *
  64  * Selecting <b>Data Structures</b> will list all C structures.
  65  *
  66  * Selecting the <b>File List</b> link will list all the source files in
  67  * the module.
  68  * Selecting a filename will show a list of all functions defined in that file.
  69  *
  70  * Selecting the <b>Data Fields</b> link will display a list of all
  71  * documented structure members.
  72  *
  73  * Selecting the <b>Globals</b> link will display a list
  74  * of all functions, structures, global variables and macros in the module.
  75  *
  76  */
  77
  78
  79 #include "glheader.h"
  80 #include "imports.h"
  81 #if FEATURE_accum
  82 #include "accum.h"
  83 #endif
  84 #include "api_exec.h"
  85 #include "arrayobj.h"
  86 #if FEATURE_attrib_stack
  87 #include "attrib.h"
  88 #endif
  89 #include "blend.h"
  90 #include "buffers.h"
  91 #include "bufferobj.h"
  92 #if FEATURE_colortable
  93 #include "colortab.h"
  94 #endif
  95 #include "context.h"
  96 #include "debug.h"
  97 #include "depth.h"
  98 #if FEATURE_dlist
  99 #include "dlist.h"
 100 #endif
 101 #if FEATURE_evaluators
 102 #include "eval.h"
 103 #endif
 104 #include "enums.h"
 105 #include "extensions.h"
 106 #include "fbobject.h"
 107 #if FEATURE_feedback
 108 #include "feedback.h"
 109 #endif
 110 #include "fog.h"
 111 #include "framebuffer.h"
 112 #include "get.h"
 113 #if FEATURE_histogram
 114 #include "histogram.h"
 115 #endif
 116 #include "hint.h"
 117 #include "hash.h"
 118 #include "light.h"
 119 #include "lines.h"
 120 #include "macros.h"
 121 #include "matrix.h"
 122 #include "multisample.h"
 123 #include "pixel.h"
 124 #include "pixelstore.h"
 125 #include "points.h"
 126 #include "polygon.h"
 127 #if FEATURE_ARB_occlusion_query
 128 #include "queryobj.h"
 129 #endif
 130 #if FEATURE_drawpix
 131 #include "rastpos.h"
 132 #endif
 133 #include "scissor.h"
 134 #include "simple_list.h"
 135 #include "state.h"
 136 #include "stencil.h"
 137 #include "texcompress.h"
 138 #include "teximage.h"
 139 #include "texobj.h"
 140 #include "texstate.h"
 141 #include "mtypes.h"
 142 #include "varray.h"
 143 #include "version.h"
 144 #include "vtxfmt.h"
 145 #include "glapi/glthread.h"
 146 #include "glapi/glapioffsets.h"
 147 #include "glapi/glapitable.h"
 148 #include "shader/program.h"
 149 #include "shader/shader_api.h"
 150 #if FEATURE_ATI_fragment_shader
 151 #include "shader/atifragshader.h"
 152 #endif
 153 #if _HAVE_FULL_GL
 154 #include "math/m_translate.h"
 155 #include "math/m_matrix.h"
 156 #include "math/m_xform.h"
 157 #include "math/mathmod.h"
 158 #endif
 159
 160 #ifdef USE_SPARC_ASM
 161 #include "sparc/sparc.h"
 162 #endif
 163
 164 #ifndef MESA_VERBOSE
 165 int MESA_VERBOSE = 0;
 166 #endif
 167
 168 #ifndef MESA_DEBUG_FLAGS
 169 int MESA_DEBUG_FLAGS = 0;
 170 #endif
 171
 172
 173 /* ubyte -> float conversion */
 174 GLfloat _mesa_ubyte_to_float_color_tab[256];
 175
 176
 177
 178 /**
 179  * Swap buffers notification callback.
 180  *
 181  * \param gc GL context.
 182  *
 183  * Called by window system just before swapping buffers.
 184  * We have to finish any pending rendering.
 185  */
 186 void
 187 _mesa_notifySwapBuffers(__GLcontext *ctx)
 188 {
 189    if (ctx->Driver.Flush) {
 190       ctx->Driver.Flush(ctx);
 191    }
 192 }
 193
 194
 195 /**********************************************************************/
 196 /** \name GL Visual allocation/destruction                            */
 197 /**********************************************************************/
 198 /*@{*/
 199
 200 /**
 201  * Allocates a GLvisual structure and initializes it via
 202  * _mesa_initialize_visual().
 203  *
 204  * \param rgbFlag GL_TRUE for RGB(A) mode, GL_FALSE for Color Index mode.
 205  * \param dbFlag double buffering
 206  * \param stereoFlag stereo buffer
 207  * \param depthBits requested bits per depth buffer value. Any value in [0, 32]
 208  * is acceptable but the actual depth type will be GLushort or GLuint as
 209  * needed.
 210  * \param stencilBits requested minimum bits per stencil buffer value
 211  * \param accumRedBits, accumGreenBits, accumBlueBits, accumAlphaBits number of bits per color component in accum buffer.
 212  * \param indexBits number of bits per pixel if \p rgbFlag is GL_FALSE
 213  * \param redBits number of bits per color component in frame buffer for RGB(A)
 214  * mode.  We always use 8 in core Mesa though.
 215  * \param greenBits same as above.
 216  * \param blueBits same as above.
 217  * \param alphaBits same as above.
 218  * \param numSamples not really used.
 219  *
 220  * \return pointer to new GLvisual or NULL if requested parameters can't be
 221  * met.
 222  *
 223  * \note Need to add params for level and numAuxBuffers (at least)
 224  */
 225 GLvisual *
 226 _mesa_create_visual( GLboolean rgbFlag,
 227                      GLboolean dbFlag,
 228                      GLboolean stereoFlag,
 229                      GLint redBits,
 230                      GLint greenBits,
 231                      GLint blueBits,
 232                      GLint alphaBits,
 233                      GLint indexBits,
 234                      GLint depthBits,
 235                      GLint stencilBits,
 236                      GLint accumRedBits,
 237                      GLint accumGreenBits,
 238                      GLint accumBlueBits,
 239                      GLint accumAlphaBits,
 240                      GLint numSamples )
 241 {
 242    GLvisual *vis = (GLvisual *) _mesa_calloc(sizeof(GLvisual));
 243    if (vis) {
 244       if (!_mesa_initialize_visual(vis, rgbFlag, dbFlag, stereoFlag,
 245                                    redBits, greenBits, blueBits, alphaBits,
 246                                    indexBits, depthBits, stencilBits,
 247                                    accumRedBits, accumGreenBits,
 248                                    accumBlueBits, accumAlphaBits,
 249                                    numSamples)) {
 250          _mesa_free(vis);
 251          return NULL;
 252       }
 253    }
 254    return vis;
 255 }
 256
 257 /**
 258  * Makes some sanity checks and fills in the fields of the
 259  * GLvisual object with the given parameters.  If the caller needs
 260  * to set additional fields, he should just probably init the whole GLvisual
 261  * object himself.
 262  * \return GL_TRUE on success, or GL_FALSE on failure.
 263  *
 264  * \sa _mesa_create_visual() above for the parameter description.
 265  */
 266 GLboolean
 267 _mesa_initialize_visual( GLvisual *vis,
 268                          GLboolean rgbFlag,
 269                          GLboolean dbFlag,
 270                          GLboolean stereoFlag,
 271                          GLint redBits,
 272                          GLint greenBits,
 273                          GLint blueBits,
 274                          GLint alphaBits,
 275                          GLint indexBits,
 276                          GLint depthBits,
 277                          GLint stencilBits,
 278                          GLint accumRedBits,
 279                          GLint accumGreenBits,
 280                          GLint accumBlueBits,
 281                          GLint accumAlphaBits,
 282                          GLint numSamples )
 283 {
 284    assert(vis);
 285
 286    if (depthBits < 0 || depthBits > 32) {
 287       return GL_FALSE;
 288    }
 289    if (stencilBits < 0 || stencilBits > STENCIL_BITS) {
 290       return GL_FALSE;
 291    }
 292    assert(accumRedBits >= 0);
 293    assert(accumGreenBits >= 0);
 294    assert(accumBlueBits >= 0);
 295    assert(accumAlphaBits >= 0);
 296
 297    vis->rgbMode          = rgbFlag;
 298    vis->doubleBufferMode = dbFlag;
 299    vis->stereoMode       = stereoFlag;
 300
 301    vis->redBits          = redBits;
 302    vis->greenBits        = greenBits;
 303    vis->blueBits         = blueBits;
 304    vis->alphaBits        = alphaBits;
 305    vis->rgbBits          = redBits + greenBits + blueBits;
 306
 307    vis->indexBits      = indexBits;
 308    vis->depthBits      = depthBits;
 309    vis->stencilBits    = stencilBits;
 310
 311    vis->accumRedBits   = accumRedBits;
 312    vis->accumGreenBits = accumGreenBits;
 313    vis->accumBlueBits  = accumBlueBits;
 314    vis->accumAlphaBits = accumAlphaBits;
 315
 316    vis->haveAccumBuffer   = accumRedBits > 0;
 317    vis->haveDepthBuffer   = depthBits > 0;
 318    vis->haveStencilBuffer = stencilBits > 0;
 319
 320    vis->numAuxBuffers = 0;
 321    vis->level = 0;
 322    vis->pixmapMode = 0;
 323    vis->sampleBuffers = numSamples > 0 ? 1 : 0;
 324    vis->samples = numSamples;
 325
 326    return GL_TRUE;
 327 }
 328
 329
 330 /**
 331  * Destroy a visual and free its memory.
 332  *
 333  * \param vis visual.
 334  *
 335  * Frees the visual structure.
 336  */
 337 void
 338 _mesa_destroy_visual( GLvisual *vis )
 339 {
 340    _mesa_free(vis);
 341 }
 342
 343 /*@}*/
 344
 345
 346 /**********************************************************************/
 347 /** \name Context allocation, initialization, destroying
 348  *
 349  * The purpose of the most initialization functions here is to provide the
 350  * default state values according to the OpenGL specification.
 351  */
 352 /**********************************************************************/
 353 /*@{*/
 354
 355 /**
 356  * One-time initialization mutex lock.
 357  *
 358  * \sa Used by one_time_init().
 359  */
 360 _glthread_DECLARE_STATIC_MUTEX(OneTimeLock);
 361
 362 /**
 363  * Calls all the various one-time-init functions in Mesa.
 364  *
 365  * While holding a global mutex lock, calls several initialization functions,
 366  * and sets the glapi callbacks if the \c MESA_DEBUG environment variable is
 367  * defined.
 368  *
 369  * \sa _math_init().
 370  */
 371 static void
 372 one_time_init( GLcontext *ctx )
 373 {
 374    static GLboolean alreadyCalled = GL_FALSE;
 375    (void) ctx;
 376    _glthread_LOCK_MUTEX(OneTimeLock);
 377    if (!alreadyCalled) {
 378       GLuint i;
 379
 380       /* do some implementation tests */
 381       assert( sizeof(GLbyte) == 1 );
 382       assert( sizeof(GLubyte) == 1 );
 383       assert( sizeof(GLshort) == 2 );
 384       assert( sizeof(GLushort) == 2 );
 385       assert( sizeof(GLint) == 4 );
 386       assert( sizeof(GLuint) == 4 );
 387
 388       _mesa_init_sqrt_table();
 389
 390 #if _HAVE_FULL_GL
 391       _math_init();
 392
 393       for (i = 0; i < 256; i++) {
 394          _mesa_ubyte_to_float_color_tab[i] = (float) i / 255.0F;
 395       }
 396 #endif
 397
 398 #ifdef USE_SPARC_ASM
 399       _mesa_init_sparc_glapi_relocs();
 400 #endif
 401       if (_mesa_getenv("MESA_DEBUG")) {
 402          _glapi_noop_enable_warnings(GL_TRUE);
 403          _glapi_set_warning_func( (_glapi_warning_func) _mesa_warning );
 404       }
 405       else {
 406          _glapi_noop_enable_warnings(GL_FALSE);
 407       }
 408
 409 #if defined(DEBUG) && defined(__DATE__) && defined(__TIME__)
 410       _mesa_debug(ctx, "Mesa %s DEBUG build %s %s\n",
 411                   MESA_VERSION_STRING, __DATE__, __TIME__);
 412 #endif
 413
 414       alreadyCalled = GL_TRUE;
 415    }
 416    _glthread_UNLOCK_MUTEX(OneTimeLock);
 417 }
 418
 419
 420 /**
 421  * Allocate and initialize a shared context state structure.
 422  * Initializes the display list, texture objects and vertex programs hash
 423  * tables, allocates the texture objects. If it runs out of memory, frees
 424  * everything already allocated before returning NULL.
 425  *
 426  * \return pointer to a gl_shared_state structure on success, or NULL on
 427  * failure.
 428  */
 429 static GLboolean
 430 alloc_shared_state( GLcontext *ctx )
 431 {
 432    struct gl_shared_state *ss = CALLOC_STRUCT(gl_shared_state);
 433    if (!ss)
 434       return GL_FALSE;
 435
 436    ctx->Shared = ss;
 437
 438    _glthread_INIT_MUTEX(ss->Mutex);
 439
 440    ss->DisplayList = _mesa_NewHashTable();
 441    ss->TexObjects = _mesa_NewHashTable();
 442    ss->Programs = _mesa_NewHashTable();
 443
 444 #if FEATURE_ARB_vertex_program
 445    ss->DefaultVertexProgram = (struct gl_vertex_program *)
 446       ctx->Driver.NewProgram(ctx, GL_VERTEX_PROGRAM_ARB, 0);
 447    if (!ss->DefaultVertexProgram)
 448       goto cleanup;
 449 #endif
 450 #if FEATURE_ARB_fragment_program
 451    ss->DefaultFragmentProgram = (struct gl_fragment_program *)
 452       ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);
 453    if (!ss->DefaultFragmentProgram)
 454       goto cleanup;
 455 #endif
 456 #if FEATURE_ATI_fragment_shader
 457    ss->ATIShaders = _mesa_NewHashTable();
 458    ss->DefaultFragmentShader = _mesa_new_ati_fragment_shader(ctx, 0);
 459    if (!ss->DefaultFragmentShader)
 460       goto cleanup;
 461 #endif
 462
 463 #if FEATURE_ARB_vertex_buffer_object || FEATURE_ARB_pixel_buffer_object
 464    ss->BufferObjects = _mesa_NewHashTable();
 465 #endif
 466
 467    ss->ArrayObjects = _mesa_NewHashTable();
 468
 469 #if FEATURE_ARB_shader_objects
 470    ss->ShaderObjects = _mesa_NewHashTable();
 471 #endif
 472
 473    ss->Default1D = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_1D);
 474    if (!ss->Default1D)
 475       goto cleanup;
 476
 477    ss->Default2D = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_2D);
 478    if (!ss->Default2D)
 479       goto cleanup;
 480
 481    ss->Default3D = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_3D);
 482    if (!ss->Default3D)
 483       goto cleanup;
 484
 485    ss->DefaultCubeMap = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_CUBE_MAP_ARB);
 486    if (!ss->DefaultCubeMap)
 487       goto cleanup;
 488
 489    ss->DefaultRect = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_RECTANGLE_NV);
 490    if (!ss->DefaultRect)
 491       goto cleanup;
 492
 493    ss->Default1DArray = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_1D_ARRAY_EXT);
 494    if (!ss->Default1DArray)
 495       goto cleanup;
 496
 497    ss->Default2DArray = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_2D_ARRAY_EXT);
 498    if (!ss->Default2DArray)
 499       goto cleanup;
 500
 501    /* sanity check */
 502    assert(ss->Default1D->RefCount == 1);
 503
 504    _glthread_INIT_MUTEX(ss->TexMutex);
 505    ss->TextureStateStamp = 0;
 506
 507 #if FEATURE_EXT_framebuffer_object
 508    ss->FrameBuffers = _mesa_NewHashTable();
 509    if (!ss->FrameBuffers)
 510       goto cleanup;
 511    ss->RenderBuffers = _mesa_NewHashTable();
 512    if (!ss->RenderBuffers)
 513       goto cleanup;
 514 #endif
 515
 516    return GL_TRUE;
 517
 518 cleanup:
 519    /* Ran out of memory at some point.  Free everything and return NULL */
 520    if (ss->DisplayList)
 521       _mesa_DeleteHashTable(ss->DisplayList);
 522    if (ss->TexObjects)
 523       _mesa_DeleteHashTable(ss->TexObjects);
 524    if (ss->Programs)
 525       _mesa_DeleteHashTable(ss->Programs);
 526 #if FEATURE_ARB_vertex_program
 527    _mesa_reference_vertprog(ctx, &ss->DefaultVertexProgram, NULL);
 528 #endif
 529 #if FEATURE_ARB_fragment_program
 530    _mesa_reference_fragprog(ctx, &ss->DefaultFragmentProgram, NULL);
 531 #endif
 532 #if FEATURE_ATI_fragment_shader
 533    if (ss->DefaultFragmentShader)
 534       _mesa_delete_ati_fragment_shader(ctx, ss->DefaultFragmentShader);
 535 #endif
 536 #if FEATURE_ARB_vertex_buffer_object || FEATURE_ARB_pixel_buffer_object
 537    if (ss->BufferObjects)
 538       _mesa_DeleteHashTable(ss->BufferObjects);
 539 #endif
 540
 541    if (ss->ArrayObjects)
 542       _mesa_DeleteHashTable (ss->ArrayObjects);
 543
 544 #if FEATURE_ARB_shader_objects
 545    if (ss->ShaderObjects)
 546       _mesa_DeleteHashTable (ss->ShaderObjects);
 547 #endif
 548
 549 #if FEATURE_EXT_framebuffer_object
 550    if (ss->FrameBuffers)
 551       _mesa_DeleteHashTable(ss->FrameBuffers);
 552    if (ss->RenderBuffers)
 553       _mesa_DeleteHashTable(ss->RenderBuffers);
 554 #endif
 555
 556    if (ss->Default1D)
 557       (*ctx->Driver.DeleteTexture)(ctx, ss->Default1D);
 558    if (ss->Default2D)
 559       (*ctx->Driver.DeleteTexture)(ctx, ss->Default2D);
 560    if (ss->Default3D)
 561       (*ctx->Driver.DeleteTexture)(ctx, ss->Default3D);
 562    if (ss->DefaultCubeMap)
 563       (*ctx->Driver.DeleteTexture)(ctx, ss->DefaultCubeMap);
 564    if (ss->DefaultRect)
 565       (*ctx->Driver.DeleteTexture)(ctx, ss->DefaultRect);
 566    if (ss->Default1DArray)
 567       (*ctx->Driver.DeleteTexture)(ctx, ss->Default1DArray);
 568    if (ss->Default2DArray)
 569       (*ctx->Driver.DeleteTexture)(ctx, ss->Default2DArray);
 570
 571    _mesa_free(ss);
 572
 573    return GL_FALSE;
 574 }
 575
 576
 577 /**
 578  * Callback for deleting a display list.  Called by _mesa_HashDeleteAll().
 579  */
 580 static void
 581 delete_displaylist_cb(GLuint id, void *data, void *userData)
 582 {
 583 #if FEATURE_dlist
 584    struct mesa_display_list *list = (struct mesa_display_list *) data;
 585    GLcontext *ctx = (GLcontext *) userData;
 586    _mesa_delete_list(ctx, list);
 587 #endif
 588 }
 589
 590 /**
 591  * Callback for deleting a texture object.  Called by _mesa_HashDeleteAll().
 592  */
 593 static void
 594 delete_texture_cb(GLuint id, void *data, void *userData)
 595 {
 596    struct gl_texture_object *texObj = (struct gl_texture_object *) data;
 597    GLcontext *ctx = (GLcontext *) userData;
 598    ctx->Driver.DeleteTexture(ctx, texObj);
 599 }
 600
 601 /**
 602  * Callback for deleting a program object.  Called by _mesa_HashDeleteAll().
 603  */
 604 static void
 605 delete_program_cb(GLuint id, void *data, void *userData)
 606 {
 607    struct gl_program *prog = (struct gl_program *) data;
 608    GLcontext *ctx = (GLcontext *) userData;
 609    ASSERT(prog->RefCount == 1); /* should only be referenced by hash table */
 610    prog->RefCount = 0;  /* now going away */
 611    ctx->Driver.DeleteProgram(ctx, prog);
 612 }
 613
 614 #if FEATURE_ATI_fragment_shader
 615 /**
 616  * Callback for deleting an ATI fragment shader object.
 617  * Called by _mesa_HashDeleteAll().
 618  */
 619 static void
 620 delete_fragshader_cb(GLuint id, void *data, void *userData)
 621 {
 622    struct ati_fragment_shader *shader = (struct ati_fragment_shader *) data;
 623    GLcontext *ctx = (GLcontext *) userData;
 624    _mesa_delete_ati_fragment_shader(ctx, shader);
 625 }
 626 #endif
 627
 628 /**
 629  * Callback for deleting a buffer object.  Called by _mesa_HashDeleteAll().
 630  */
 631 static void
 632 delete_bufferobj_cb(GLuint id, void *data, void *userData)
 633 {
 634    struct gl_buffer_object *bufObj = (struct gl_buffer_object *) data;
 635    GLcontext *ctx = (GLcontext *) userData;
 636    ctx->Driver.DeleteBuffer(ctx, bufObj);
 637 }
 638
 639 /**
 640  * Callback for deleting an array object.  Called by _mesa_HashDeleteAll().
 641  */
 642 static void
 643 delete_arrayobj_cb(GLuint id, void *data, void *userData)
 644 {
 645    struct gl_array_object *arrayObj = (struct gl_array_object *) data;
 646    GLcontext *ctx = (GLcontext *) userData;
 647    _mesa_delete_array_object(ctx, arrayObj);
 648 }
 649
 650 /**
 651  * Callback for freeing shader program data. Call it before delete_shader_cb
 652  * to avoid memory access error.
 653  */
 654 static void
 655 free_shader_program_data_cb(GLuint id, void *data, void *userData)
 656 {
 657    GLcontext *ctx = (GLcontext *) userData;
 658    struct gl_shader_program *shProg = (struct gl_shader_program *) data;
 659
 660    if (shProg->Type == GL_SHADER_PROGRAM_MESA) {
 661        _mesa_free_shader_program_data(ctx, shProg);
 662    }
 663 }
 664
 665 /**
 666  * Callback for deleting shader and shader programs objects.
 667  * Called by _mesa_HashDeleteAll().
 668  */
 669 static void
 670 delete_shader_cb(GLuint id, void *data, void *userData)
 671 {
 672    GLcontext *ctx = (GLcontext *) userData;
 673    struct gl_shader *sh = (struct gl_shader *) data;
 674    if (sh->Type == GL_FRAGMENT_SHADER || sh->Type == GL_VERTEX_SHADER) {
 675       _mesa_free_shader(ctx, sh);
 676    }
 677    else {
 678       struct gl_shader_program *shProg = (struct gl_shader_program *) data;
 679       ASSERT(shProg->Type == GL_SHADER_PROGRAM_MESA);
 680       _mesa_free_shader_program(ctx, shProg);
 681    }
 682 }
 683
 684 /**
 685  * Callback for deleting a framebuffer object.  Called by _mesa_HashDeleteAll()
 686  */
 687 static void
 688 delete_framebuffer_cb(GLuint id, void *data, void *userData)
 689 {
 690    struct gl_framebuffer *fb = (struct gl_framebuffer *) data;
 691    /* The fact that the framebuffer is in the hashtable means its refcount
 692     * is one, but we're removing from the hashtable now.  So clear refcount.
 693     */
 694    /*assert(fb->RefCount == 1);*/
 695    fb->RefCount = 0;
 696
 697    /* NOTE: Delete should always be defined but there are two reports
 698     * of it being NULL (bugs 13507, 14293).  Work-around for now.
 699     */
 700    if (fb->Delete)
 701       fb->Delete(fb);
 702 }
 703
 704 /**
 705  * Callback for deleting a renderbuffer object. Called by _mesa_HashDeleteAll()
 706  */
 707 static void
 708 delete_renderbuffer_cb(GLuint id, void *data, void *userData)
 709 {
 710    struct gl_renderbuffer *rb = (struct gl_renderbuffer *) data;
 711    rb->RefCount = 0;  /* see comment for FBOs above */
 712    if (rb->Delete)
 713       rb->Delete(rb);
 714 }
 715
 716
 717 /**
 718  * Deallocate a shared state object and all children structures.
 719  *
 720  * \param ctx GL context.
 721  * \param ss shared state pointer.
 722  *
 723  * Frees the display lists, the texture objects (calling the driver texture
 724  * deletion callback to free its private data) and the vertex programs, as well
 725  * as their hash tables.
 726  *
 727  * \sa alloc_shared_state().
 728  */
 729 static void
 730 free_shared_state( GLcontext *ctx, struct gl_shared_state *ss )
 731 {
 732    /*
 733     * Free display lists
 734     */
 735    _mesa_HashDeleteAll(ss->DisplayList, delete_displaylist_cb, ctx);
 736    _mesa_DeleteHashTable(ss->DisplayList);
 737
 738 #if FEATURE_ARB_shader_objects
 739    _mesa_HashWalk(ss->ShaderObjects, free_shader_program_data_cb, ctx);
 740    _mesa_HashDeleteAll(ss->ShaderObjects, delete_shader_cb, ctx);
 741    _mesa_DeleteHashTable(ss->ShaderObjects);
 742 #endif
 743
 744    _mesa_HashDeleteAll(ss->Programs, delete_program_cb, ctx);
 745    _mesa_DeleteHashTable(ss->Programs);
 746
 747 #if FEATURE_ARB_vertex_program
 748    _mesa_reference_vertprog(ctx, &ss->DefaultVertexProgram, NULL);
 749 #endif
 750 #if FEATURE_ARB_fragment_program
 751    _mesa_reference_fragprog(ctx, &ss->DefaultFragmentProgram, NULL);
 752 #endif
 753
 754 #if FEATURE_ATI_fragment_shader
 755    _mesa_HashDeleteAll(ss->ATIShaders, delete_fragshader_cb, ctx);
 756    _mesa_DeleteHashTable(ss->ATIShaders);
 757    _mesa_delete_ati_fragment_shader(ctx, ss->DefaultFragmentShader);
 758 #endif
 759
 760 #if FEATURE_ARB_vertex_buffer_object || FEATURE_ARB_pixel_buffer_object
 761    _mesa_HashDeleteAll(ss->BufferObjects, delete_bufferobj_cb, ctx);
 762    _mesa_DeleteHashTable(ss->BufferObjects);
 763 #endif
 764
 765    _mesa_HashDeleteAll(ss->ArrayObjects, delete_arrayobj_cb, ctx);
 766    _mesa_DeleteHashTable(ss->ArrayObjects);
 767
 768 #if FEATURE_EXT_framebuffer_object
 769    _mesa_HashDeleteAll(ss->FrameBuffers, delete_framebuffer_cb, ctx);
 770    _mesa_DeleteHashTable(ss->FrameBuffers);
 771    _mesa_HashDeleteAll(ss->RenderBuffers, delete_renderbuffer_cb, ctx);
 772    _mesa_DeleteHashTable(ss->RenderBuffers);
 773 #endif
 774
 775    /*
 776     * Free texture objects (after FBOs since some textures might have
 777     * been bound to FBOs).
 778     */
 779    ASSERT(ctx->Driver.DeleteTexture);
 780    /* the default textures */
 781    ctx->Driver.DeleteTexture(ctx, ss->Default1D);
 782    ctx->Driver.DeleteTexture(ctx, ss->Default2D);
 783    ctx->Driver.DeleteTexture(ctx, ss->Default3D);
 784    ctx->Driver.DeleteTexture(ctx, ss->DefaultCubeMap);
 785    ctx->Driver.DeleteTexture(ctx, ss->DefaultRect);
 786    ctx->Driver.DeleteTexture(ctx, ss->Default1DArray);
 787    ctx->Driver.DeleteTexture(ctx, ss->Default2DArray);
 788    /* all other textures */
 789    _mesa_HashDeleteAll(ss->TexObjects, delete_texture_cb, ctx);
 790    _mesa_DeleteHashTable(ss->TexObjects);
 791
 792    _glthread_DESTROY_MUTEX(ss->Mutex);
 793
 794    _mesa_free(ss);
 795 }
 796
 797
 798 /**
 799  * Initialize fields of gl_current_attrib (aka ctx->Current.*)
 800  */
 801 static void
 802 _mesa_init_current(GLcontext *ctx)
 803 {
 804    GLuint i;
 805
 806    /* Init all to (0,0,0,1) */
 807    for (i = 0; i < VERT_ATTRIB_MAX; i++) {
 808       ASSIGN_4V( ctx->Current.Attrib[i], 0.0, 0.0, 0.0, 1.0 );
 809    }
 810
 811    /* redo special cases: */
 812    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_WEIGHT], 1.0, 0.0, 0.0, 0.0 );
 813    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_NORMAL], 0.0, 0.0, 1.0, 1.0 );
 814    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR0], 1.0, 1.0, 1.0, 1.0 );
 815    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR1], 0.0, 0.0, 0.0, 1.0 );
 816    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR_INDEX], 1.0, 0.0, 0.0, 1.0 );
 817    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_EDGEFLAG], 1.0, 0.0, 0.0, 1.0 );
 818 }
 819
 820
 821 /**
 822  * Init vertex/fragment program native limits from logical limits.
 823  */
 824 static void
 825 init_natives(struct gl_program_constants *prog)
 826 {
 827    prog->MaxNativeInstructions = prog->MaxInstructions;
 828    prog->MaxNativeAluInstructions = prog->MaxAluInstructions;
 829    prog->MaxNativeTexInstructions = prog->MaxTexInstructions;
 830    prog->MaxNativeTexIndirections = prog->MaxTexIndirections;
 831    prog->MaxNativeAttribs = prog->MaxAttribs;
 832    prog->MaxNativeTemps = prog->MaxTemps;
 833    prog->MaxNativeAddressRegs = prog->MaxAddressRegs;
 834    prog->MaxNativeParameters = prog->MaxParameters;
 835 }
 836
 837
 838 /**
 839  * Initialize fields of gl_constants (aka ctx->Const.*).
 840  * Use defaults from config.h.  The device drivers will often override
 841  * some of these values (such as number of texture units).
 842  */
 843 static void
 844 _mesa_init_constants(GLcontext *ctx)
 845 {
 846    assert(ctx);
 847
 848    assert(MAX_TEXTURE_LEVELS >= MAX_3D_TEXTURE_LEVELS);
 849    assert(MAX_TEXTURE_LEVELS >= MAX_CUBE_TEXTURE_LEVELS);
 850
 851    assert(MAX_TEXTURE_UNITS >= MAX_TEXTURE_COORD_UNITS);
 852    assert(MAX_TEXTURE_UNITS >= MAX_TEXTURE_IMAGE_UNITS);
 853
 854    /* Constants, may be overriden (usually only reduced) by device drivers */
 855    ctx->Const.MaxTextureLevels = MAX_TEXTURE_LEVELS;
 856    ctx->Const.Max3DTextureLevels = MAX_3D_TEXTURE_LEVELS;
 857    ctx->Const.MaxCubeTextureLevels = MAX_CUBE_TEXTURE_LEVELS;
 858    ctx->Const.MaxTextureRectSize = MAX_TEXTURE_RECT_SIZE;
 859    ctx->Const.MaxArrayTextureLayers = MAX_ARRAY_TEXTURE_LAYERS;
 860    ctx->Const.MaxTextureCoordUnits = MAX_TEXTURE_COORD_UNITS;
 861    ctx->Const.MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 862    ctx->Const.MaxTextureUnits = MIN2(ctx->Const.MaxTextureCoordUnits,
 863                                      ctx->Const.MaxTextureImageUnits);
 864    ctx->Const.MaxTextureMaxAnisotropy = MAX_TEXTURE_MAX_ANISOTROPY;
 865    ctx->Const.MaxTextureLodBias = MAX_TEXTURE_LOD_BIAS;
 866    ctx->Const.MaxArrayLockSize = MAX_ARRAY_LOCK_SIZE;
 867    ctx->Const.SubPixelBits = SUB_PIXEL_BITS;
 868    ctx->Const.MinPointSize = MIN_POINT_SIZE;
 869    ctx->Const.MaxPointSize = MAX_POINT_SIZE;
 870    ctx->Const.MinPointSizeAA = MIN_POINT_SIZE;
 871    ctx->Const.MaxPointSizeAA = MAX_POINT_SIZE;
 872    ctx->Const.PointSizeGranularity = (GLfloat) POINT_SIZE_GRANULARITY;
 873    ctx->Const.MinLineWidth = MIN_LINE_WIDTH;
 874    ctx->Const.MaxLineWidth = MAX_LINE_WIDTH;
 875    ctx->Const.MinLineWidthAA = MIN_LINE_WIDTH;
 876    ctx->Const.MaxLineWidthAA = MAX_LINE_WIDTH;
 877    ctx->Const.LineWidthGranularity = (GLfloat) LINE_WIDTH_GRANULARITY;
 878    ctx->Const.MaxColorTableSize = MAX_COLOR_TABLE_SIZE;
 879    ctx->Const.MaxConvolutionWidth = MAX_CONVOLUTION_WIDTH;
 880    ctx->Const.MaxConvolutionHeight = MAX_CONVOLUTION_HEIGHT;
 881    ctx->Const.MaxClipPlanes = MAX_CLIP_PLANES;
 882    ctx->Const.MaxLights = MAX_LIGHTS;
 883    ctx->Const.MaxShininess = 128.0;
 884    ctx->Const.MaxSpotExponent = 128.0;
 885    ctx->Const.MaxViewportWidth = MAX_WIDTH;
 886    ctx->Const.MaxViewportHeight = MAX_HEIGHT;
 887 #if FEATURE_ARB_vertex_program
 888    ctx->Const.VertexProgram.MaxInstructions = MAX_NV_VERTEX_PROGRAM_INSTRUCTIONS;
 889    ctx->Const.VertexProgram.MaxAluInstructions = 0;
 890    ctx->Const.VertexProgram.MaxTexInstructions = 0;
 891    ctx->Const.VertexProgram.MaxTexIndirections = 0;
 892    ctx->Const.VertexProgram.MaxAttribs = MAX_NV_VERTEX_PROGRAM_INPUTS;
 893    ctx->Const.VertexProgram.MaxTemps = MAX_PROGRAM_TEMPS;
 894    ctx->Const.VertexProgram.MaxParameters = MAX_NV_VERTEX_PROGRAM_PARAMS;
 895    ctx->Const.VertexProgram.MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
 896    ctx->Const.VertexProgram.MaxEnvParams = MAX_PROGRAM_ENV_PARAMS;
 897    ctx->Const.VertexProgram.MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 898    ctx->Const.VertexProgram.MaxUniformComponents = 4 * MAX_UNIFORMS;
 899    init_natives(&ctx->Const.VertexProgram);
 900 #endif
 901
 902 #if FEATURE_ARB_fragment_program
 903    ctx->Const.FragmentProgram.MaxInstructions = MAX_NV_FRAGMENT_PROGRAM_INSTRUCTIONS;
 904    ctx->Const.FragmentProgram.MaxAluInstructions = MAX_FRAGMENT_PROGRAM_ALU_INSTRUCTIONS;
 905    ctx->Const.FragmentProgram.MaxTexInstructions = MAX_FRAGMENT_PROGRAM_TEX_INSTRUCTIONS;
 906    ctx->Const.FragmentProgram.MaxTexIndirections = MAX_FRAGMENT_PROGRAM_TEX_INDIRECTIONS;
 907    ctx->Const.FragmentProgram.MaxAttribs = MAX_NV_FRAGMENT_PROGRAM_INPUTS;
 908    ctx->Const.FragmentProgram.MaxTemps = MAX_PROGRAM_TEMPS;
 909    ctx->Const.FragmentProgram.MaxParameters = MAX_NV_FRAGMENT_PROGRAM_PARAMS;
 910    ctx->Const.FragmentProgram.MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
 911    ctx->Const.FragmentProgram.MaxEnvParams = MAX_PROGRAM_ENV_PARAMS;
 912    ctx->Const.FragmentProgram.MaxAddressRegs = MAX_FRAGMENT_PROGRAM_ADDRESS_REGS;
 913    ctx->Const.FragmentProgram.MaxUniformComponents = 4 * MAX_UNIFORMS;
 914    init_natives(&ctx->Const.FragmentProgram);
 915 #endif
 916    ctx->Const.MaxProgramMatrices = MAX_PROGRAM_MATRICES;
 917    ctx->Const.MaxProgramMatrixStackDepth = MAX_PROGRAM_MATRIX_STACK_DEPTH;
 918
 919    /* CheckArrayBounds is overriden by drivers/x11 for X server */
 920    ctx->Const.CheckArrayBounds = GL_FALSE;
 921
 922    /* GL_ARB_draw_buffers */
 923    ctx->Const.MaxDrawBuffers = MAX_DRAW_BUFFERS;
 924
 925    /* GL_OES_read_format */
 926    ctx->Const.ColorReadFormat = GL_RGBA;
 927    ctx->Const.ColorReadType = GL_UNSIGNED_BYTE;
 928
 929 #if FEATURE_EXT_framebuffer_object
 930    ctx->Const.MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
 931    ctx->Const.MaxRenderbufferSize = MAX_WIDTH;
 932 #endif
 933
 934 #if FEATURE_ARB_vertex_shader
 935    ctx->Const.MaxVertexTextureImageUnits = MAX_VERTEX_TEXTURE_IMAGE_UNITS;
 936    ctx->Const.MaxVarying = MAX_VARYING;
 937 #endif
 938
 939    /* sanity checks */
 940    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
 941                                              ctx->Const.MaxTextureCoordUnits));
 942    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 943    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 944
 945    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 946    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 947    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
 948    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
 949 }
 950
 951
 952 /**
 953  * Do some sanity checks on the limits/constants for the given context.
 954  * Only called the first time a context is bound.
 955  */
 956 static void
 957 check_context_limits(GLcontext *ctx)
 958 {
 959    /* Many context limits/constants are limited by the size of
 960     * internal arrays.
 961     */
 962    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 963    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 964    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 965    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 966
 967    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
 968    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
 969
 970    /* make sure largest texture image is <= MAX_WIDTH in size */
 971    assert((1 << (ctx->Const.MaxTextureLevels -1 )) <= MAX_WIDTH);
 972    assert((1 << (ctx->Const.MaxCubeTextureLevels -1 )) <= MAX_WIDTH);
 973    assert((1 << (ctx->Const.Max3DTextureLevels -1 )) <= MAX_WIDTH);
 974
 975    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 976
 977    /* XXX probably add more tests */
 978 }
 979
 980
 981 /**
 982  * Initialize the attribute groups in a GL context.
 983  *
 984  * \param ctx GL context.
 985  *
 986  * Initializes all the attributes, calling the respective <tt>init*</tt>
 987  * functions for the more complex data structures.
 988  */
 989 static GLboolean
 990 init_attrib_groups(GLcontext *ctx)
 991 {
 992    assert(ctx);
 993
 994    /* Constants */
 995    _mesa_init_constants( ctx );
 996
 997    /* Extensions */
 998    _mesa_init_extensions( ctx );
 999
1000    /* Attribute Groups */
1001 #if FEATURE_accum
1002    _mesa_init_accum( ctx );
1003 #endif
1004 #if FEATURE_attrib_stack
1005    _mesa_init_attrib( ctx );
1006 #endif
1007    _mesa_init_buffer_objects( ctx );
1008    _mesa_init_color( ctx );
1009 #if FEATURE_colortable
1010    _mesa_init_colortables( ctx );
1011 #endif
1012    _mesa_init_current( ctx );
1013    _mesa_init_depth( ctx );
1014    _mesa_init_debug( ctx );
1015 #if FEATURE_dlist
1016    _mesa_init_display_list( ctx );
1017 #endif
1018 #if FEATURE_evaluators
1019    _mesa_init_eval( ctx );
1020 #endif
1021    _mesa_init_fbobjects( ctx );
1022 #if FEATURE_feedback
1023    _mesa_init_feedback( ctx );
1024 #else
1025    ctx->RenderMode = GL_RENDER;
1026 #endif
1027    _mesa_init_fog( ctx );
1028 #if FEATURE_histogram
1029    _mesa_init_histogram( ctx );
1030 #endif
1031    _mesa_init_hint( ctx );
1032    _mesa_init_line( ctx );
1033    _mesa_init_lighting( ctx );
1034    _mesa_init_matrix( ctx );
1035    _mesa_init_multisample( ctx );
1036    _mesa_init_pixel( ctx );
1037    _mesa_init_pixelstore( ctx );
1038    _mesa_init_point( ctx );
1039    _mesa_init_polygon( ctx );
1040    _mesa_init_program( ctx );
1041 #if FEATURE_ARB_occlusion_query
1042    _mesa_init_query( ctx );
1043 #endif
1044 #if FEATURE_drawpix
1045    _mesa_init_rastpos( ctx );
1046 #endif
1047    _mesa_init_scissor( ctx );
1048    _mesa_init_shader_state( ctx );
1049    _mesa_init_stencil( ctx );
1050    _mesa_init_transform( ctx );
1051    _mesa_init_varray( ctx );
1052    _mesa_init_viewport( ctx );
1053
1054    if (!_mesa_init_texture( ctx ))
1055       return GL_FALSE;
1056
1057 #if FEATURE_texture_s3tc
1058    _mesa_init_texture_s3tc( ctx );
1059 #endif
1060 #if FEATURE_texture_fxt1
1061    _mesa_init_texture_fxt1( ctx );
1062 #endif
1063
1064    /* Miscellaneous */
1065    ctx->NewState = _NEW_ALL;
1066    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
1067
1068    return GL_TRUE;
1069 }
1070
1071
1072 /**
1073  * Update default objects in a GL context with respect to shared state.
1074  *
1075  * \param ctx GL context.
1076  *
1077  * Removes references to old default objects, (texture objects, program
1078  * objects, etc.) and changes to reference those from the current shared
1079  * state.
1080  */
1081 static GLboolean
1082 update_default_objects(GLcontext *ctx)
1083 {
1084    assert(ctx);
1085
1086    _mesa_update_default_objects_program(ctx);
1087    _mesa_update_default_objects_texture(ctx);
1088    _mesa_update_default_objects_buffer_objects(ctx);
1089
1090    return GL_TRUE;
1091 }
1092
1093
1094 /**
1095  * This is the default function we plug into all dispatch table slots
1096  * This helps prevents a segfault when someone calls a GL function without
1097  * first checking if the extension's supported.
1098  */
1099 static int
1100 generic_nop(void)
1101 {
1102    _mesa_warning(NULL, "User called no-op dispatch function (an unsupported extension function?)");
1103    return 0;
1104 }
1105
1106
1107 /**
1108  * Allocate and initialize a new dispatch table.
1109  */
1110 static struct _glapi_table *
1111 alloc_dispatch_table(void)
1112 {
1113    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
1114     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
1115     * Mesa we do this to accomodate different versions of libGL and various
1116     * DRI drivers.
1117     */
1118    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
1119                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
1120    struct _glapi_table *table =
1121       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
1122    if (table) {
1123       _glapi_proc *entry = (_glapi_proc *) table;
1124       GLint i;
1125       for (i = 0; i < numEntries; i++) {
1126          entry[i] = (_glapi_proc) generic_nop;
1127       }
1128    }
1129    return table;
1130 }
1131
1132
1133 /**
1134  * Initialize a GLcontext struct (rendering context).
1135  *
1136  * This includes allocating all the other structs and arrays which hang off of
1137  * the context by pointers.
1138  * Note that the driver needs to pass in its dd_function_table here since
1139  * we need to at least call driverFunctions->NewTextureObject to create the
1140  * default texture objects.
1141  *
1142  * Called by _mesa_create_context().
1143  *
1144  * Performs the imports and exports callback tables initialization, and
1145  * miscellaneous one-time initializations. If no shared context is supplied one
1146  * is allocated, and increase its reference count.  Setups the GL API dispatch
1147  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
1148  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
1149  * for debug flags.
1150  *
1151  * \param ctx the context to initialize
1152  * \param visual describes the visual attributes for this context
1153  * \param share_list points to context to share textures, display lists,
1154  *        etc with, or NULL
1155  * \param driverFunctions table of device driver functions for this context
1156  *        to use
1157  * \param driverContext pointer to driver-specific context data
1158  */
1159 GLboolean
1160 _mesa_initialize_context(GLcontext *ctx,
1161                          const GLvisual *visual,
1162                          GLcontext *share_list,
1163                          const struct dd_function_table *driverFunctions,
1164                          void *driverContext)
1165 {
1166    /*ASSERT(driverContext);*/
1167    assert(driverFunctions->NewTextureObject);
1168    assert(driverFunctions->FreeTexImageData);
1169
1170    /* misc one-time initializations */
1171    one_time_init(ctx);
1172
1173    ctx->Visual = *visual;
1174    ctx->DrawBuffer = NULL;
1175    ctx->ReadBuffer = NULL;
1176    ctx->WinSysDrawBuffer = NULL;
1177    ctx->WinSysReadBuffer = NULL;
1178
1179    /* Plug in driver functions and context pointer here.
1180     * This is important because when we call alloc_shared_state() below
1181     * we'll call ctx->Driver.NewTextureObject() to create the default
1182     * textures.
1183     */
1184    ctx->Driver = *driverFunctions;
1185    ctx->DriverCtx = driverContext;
1186
1187    if (share_list) {
1188       /* share state with another context */
1189       ctx->Shared = share_list->Shared;
1190    }
1191    else {
1192       /* allocate new, unshared state */
1193       if (!alloc_shared_state( ctx )) {
1194          return GL_FALSE;
1195       }
1196    }
1197    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1198    ctx->Shared->RefCount++;
1199    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1200
1201    if (!init_attrib_groups( ctx )) {
1202       free_shared_state(ctx, ctx->Shared);
1203       return GL_FALSE;
1204    }
1205
1206    /* setup the API dispatch tables */
1207    ctx->Exec = alloc_dispatch_table();
1208    ctx->Save = alloc_dispatch_table();
1209    if (!ctx->Exec || !ctx->Save) {
1210       free_shared_state(ctx, ctx->Shared);
1211       if (ctx->Exec)
1212          _mesa_free(ctx->Exec);
1213    }
1214 #if FEATURE_dispatch
1215    _mesa_init_exec_table(ctx->Exec);
1216 #endif
1217    ctx->CurrentDispatch = ctx->Exec;
1218 #if FEATURE_dlist
1219    _mesa_init_dlist_table(ctx->Save);
1220    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
1221 #endif
1222    /* Neutral tnl module stuff */
1223    _mesa_init_exec_vtxfmt( ctx );
1224    ctx->TnlModule.Current = NULL;
1225    ctx->TnlModule.SwapCount = 0;
1226
1227    ctx->FragmentProgram._MaintainTexEnvProgram
1228       = (_mesa_getenv("MESA_TEX_PROG") != NULL);
1229    ctx->FragmentProgram._UseTexEnvProgram = ctx->FragmentProgram._MaintainTexEnvProgram;
1230
1231    ctx->VertexProgram._MaintainTnlProgram
1232       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
1233    if (ctx->VertexProgram._MaintainTnlProgram) {
1234       /* this is required... */
1235       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
1236    }
1237
1238 #ifdef FEATURE_extra_context_init
1239    _mesa_initialize_context_extra(ctx);
1240 #endif
1241
1242    ctx->FirstTimeCurrent = GL_TRUE;
1243
1244    return GL_TRUE;
1245 }
1246
1247
1248 /**
1249  * Allocate and initialize a GLcontext structure.
1250  * Note that the driver needs to pass in its dd_function_table here since
1251  * we need to at least call driverFunctions->NewTextureObject to initialize
1252  * the rendering context.
1253  *
1254  * \param visual a GLvisual pointer (we copy the struct contents)
1255  * \param share_list another context to share display lists with or NULL
1256  * \param driverFunctions points to the dd_function_table into which the
1257  *        driver has plugged in all its special functions.
1258  * \param driverCtx points to the device driver's private context state
1259  *
1260  * \return pointer to a new __GLcontextRec or NULL if error.
1261  */
1262 GLcontext *
1263 _mesa_create_context(const GLvisual *visual,
1264                      GLcontext *share_list,
1265                      const struct dd_function_table *driverFunctions,
1266                      void *driverContext)
1267 {
1268    GLcontext *ctx;
1269
1270    ASSERT(visual);
1271    /*ASSERT(driverContext);*/
1272
1273    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
1274    if (!ctx)
1275       return NULL;
1276
1277    if (_mesa_initialize_context(ctx, visual, share_list,
1278                                 driverFunctions, driverContext)) {
1279       return ctx;
1280    }
1281    else {
1282       _mesa_free(ctx);
1283       return NULL;
1284    }
1285 }
1286
1287
1288 /**
1289  * Free the data associated with the given context.
1290  *
1291  * But doesn't free the GLcontext struct itself.
1292  *
1293  * \sa _mesa_initialize_context() and init_attrib_groups().
1294  */
1295 void
1296 _mesa_free_context_data( GLcontext *ctx )
1297 {
1298    if (!_mesa_get_current_context()){
1299       /* No current context, but we may need one in order to delete
1300        * texture objs, etc.  So temporarily bind the context now.
1301        */
1302       _mesa_make_current(ctx, NULL, NULL);
1303    }
1304
1305    /* unreference WinSysDraw/Read buffers */
1306    _mesa_unreference_framebuffer(&ctx->WinSysDrawBuffer);
1307    _mesa_unreference_framebuffer(&ctx->WinSysReadBuffer);
1308    _mesa_unreference_framebuffer(&ctx->DrawBuffer);
1309    _mesa_unreference_framebuffer(&ctx->ReadBuffer);
1310
1311    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
1312    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
1313    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
1314
1315    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
1316    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
1317    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
1318
1319    _mesa_free_attrib_data(ctx);
1320    _mesa_free_lighting_data( ctx );
1321 #if FEATURE_evaluators
1322    _mesa_free_eval_data( ctx );
1323 #endif
1324    _mesa_free_texture_data( ctx );
1325    _mesa_free_matrix_data( ctx );
1326    _mesa_free_viewport_data( ctx );
1327 #if FEATURE_colortable
1328    _mesa_free_colortables_data( ctx );
1329 #endif
1330    _mesa_free_program_data(ctx);
1331    _mesa_free_shader_state(ctx);
1332 #if FEATURE_ARB_occlusion_query
1333    _mesa_free_query_data(ctx);
1334 #endif
1335
1336 #if FEATURE_ARB_vertex_buffer_object
1337    _mesa_delete_buffer_object(ctx, ctx->Array.NullBufferObj);
1338 #endif
1339    _mesa_delete_array_object(ctx, ctx->Array.DefaultArrayObj);
1340
1341    /* free dispatch tables */
1342    _mesa_free(ctx->Exec);
1343    _mesa_free(ctx->Save);
1344
1345    /* Shared context state (display lists, textures, etc) */
1346    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1347    ctx->Shared->RefCount--;
1348    assert(ctx->Shared->RefCount >= 0);
1349    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1350    if (ctx->Shared->RefCount == 0) {
1351       /* free shared state */
1352       free_shared_state( ctx, ctx->Shared );
1353    }
1354
1355    if (ctx->Extensions.String)
1356       _mesa_free((void *) ctx->Extensions.String);
1357
1358    /* unbind the context if it's currently bound */
1359    if (ctx == _mesa_get_current_context()) {
1360       _mesa_make_current(NULL, NULL, NULL);
1361    }
1362 }
1363
1364
1365 /**
1366  * Destroy a GLcontext structure.
1367  *
1368  * \param ctx GL context.
1369  *
1370  * Calls _mesa_free_context_data() and frees the GLcontext structure itself.
1371  */
1372 void
1373 _mesa_destroy_context( GLcontext *ctx )
1374 {
1375    if (ctx) {
1376       _mesa_free_context_data(ctx);
1377       _mesa_free( (void *) ctx );
1378    }
1379 }
1380
1381
1382 #if _HAVE_FULL_GL
1383 /**
1384  * Copy attribute groups from one context to another.
1385  *
1386  * \param src source context
1387  * \param dst destination context
1388  * \param mask bitwise OR of GL_*_BIT flags
1389  *
1390  * According to the bits specified in \p mask, copies the corresponding
1391  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1392  * memcpy is not enough due to the existence of internal pointers in their data
1393  * structures.
1394  */
1395 void
1396 _mesa_copy_context( const GLcontext *src, GLcontext *dst, GLuint mask )
1397 {
1398    if (mask & GL_ACCUM_BUFFER_BIT) {
1399       /* OK to memcpy */
1400       dst->Accum = src->Accum;
1401    }
1402    if (mask & GL_COLOR_BUFFER_BIT) {
1403       /* OK to memcpy */
1404       dst->Color = src->Color;
1405    }
1406    if (mask & GL_CURRENT_BIT) {
1407       /* OK to memcpy */
1408       dst->Current = src->Current;
1409    }
1410    if (mask & GL_DEPTH_BUFFER_BIT) {
1411       /* OK to memcpy */
1412       dst->Depth = src->Depth;
1413    }
1414    if (mask & GL_ENABLE_BIT) {
1415       /* no op */
1416    }
1417    if (mask & GL_EVAL_BIT) {
1418       /* OK to memcpy */
1419       dst->Eval = src->Eval;
1420    }
1421    if (mask & GL_FOG_BIT) {
1422       /* OK to memcpy */
1423       dst->Fog = src->Fog;
1424    }
1425    if (mask & GL_HINT_BIT) {
1426       /* OK to memcpy */
1427       dst->Hint = src->Hint;
1428    }
1429    if (mask & GL_LIGHTING_BIT) {
1430       GLuint i;
1431       /* begin with memcpy */
1432       dst->Light = src->Light;
1433       /* fixup linked lists to prevent pointer insanity */
1434       make_empty_list( &(dst->Light.EnabledList) );
1435       for (i = 0; i < MAX_LIGHTS; i++) {
1436          if (dst->Light.Light[i].Enabled) {
1437             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1438          }
1439       }
1440    }
1441    if (mask & GL_LINE_BIT) {
1442       /* OK to memcpy */
1443       dst->Line = src->Line;
1444    }
1445    if (mask & GL_LIST_BIT) {
1446       /* OK to memcpy */
1447       dst->List = src->List;
1448    }
1449    if (mask & GL_PIXEL_MODE_BIT) {
1450       /* OK to memcpy */
1451       dst->Pixel = src->Pixel;
1452    }
1453    if (mask & GL_POINT_BIT) {
1454       /* OK to memcpy */
1455       dst->Point = src->Point;
1456    }
1457    if (mask & GL_POLYGON_BIT) {
1458       /* OK to memcpy */
1459       dst->Polygon = src->Polygon;
1460    }
1461    if (mask & GL_POLYGON_STIPPLE_BIT) {
1462       /* Use loop instead of MEMCPY due to problem with Portland Group's
1463        * C compiler.  Reported by John Stone.
1464        */
1465       GLuint i;
1466       for (i = 0; i < 32; i++) {
1467          dst->PolygonStipple[i] = src->PolygonStipple[i];
1468       }
1469    }
1470    if (mask & GL_SCISSOR_BIT) {
1471       /* OK to memcpy */
1472       dst->Scissor = src->Scissor;
1473    }
1474    if (mask & GL_STENCIL_BUFFER_BIT) {
1475       /* OK to memcpy */
1476       dst->Stencil = src->Stencil;
1477    }
1478    if (mask & GL_TEXTURE_BIT) {
1479       /* Cannot memcpy because of pointers */
1480       _mesa_copy_texture_state(src, dst);
1481    }
1482    if (mask & GL_TRANSFORM_BIT) {
1483       /* OK to memcpy */
1484       dst->Transform = src->Transform;
1485    }
1486    if (mask & GL_VIEWPORT_BIT) {
1487       /* Cannot use memcpy, because of pointers in GLmatrix _WindowMap */
1488       dst->Viewport.X = src->Viewport.X;
1489       dst->Viewport.Y = src->Viewport.Y;
1490       dst->Viewport.Width = src->Viewport.Width;
1491       dst->Viewport.Height = src->Viewport.Height;
1492       dst->Viewport.Near = src->Viewport.Near;
1493       dst->Viewport.Far = src->Viewport.Far;
1494       _math_matrix_copy(&dst->Viewport._WindowMap, &src->Viewport._WindowMap);
1495    }
1496
1497    /* XXX FIXME:  Call callbacks?
1498     */
1499    dst->NewState = _NEW_ALL;
1500 }
1501 #endif
1502
1503
1504 /**
1505  * Check if the given context can render into the given framebuffer
1506  * by checking visual attributes.
1507  *
1508  * Most of these tests could go away because Mesa is now pretty flexible
1509  * in terms of mixing rendering contexts with framebuffers.  As long
1510  * as RGB vs. CI mode agree, we're probably good.
1511  *
1512  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1513  */
1514 static GLboolean
1515 check_compatible(const GLcontext *ctx, const GLframebuffer *buffer)
1516 {
1517    const GLvisual *ctxvis = &ctx->Visual;
1518    const GLvisual *bufvis = &buffer->Visual;
1519
1520    if (ctxvis == bufvis)
1521       return GL_TRUE;
1522
1523    if (ctxvis->rgbMode != bufvis->rgbMode)
1524       return GL_FALSE;
1525 #if 0
1526    /* disabling this fixes the fgl_glxgears pbuffer demo */
1527    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1528       return GL_FALSE;
1529 #endif
1530    if (ctxvis->stereoMode && !bufvis->stereoMode)
1531       return GL_FALSE;
1532    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1533       return GL_FALSE;
1534    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1535       return GL_FALSE;
1536    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1537       return GL_FALSE;
1538    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1539       return GL_FALSE;
1540    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1541       return GL_FALSE;
1542    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1543       return GL_FALSE;
1544 #if 0
1545    /* disabled (see bug 11161) */
1546    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1547       return GL_FALSE;
1548 #endif
1549    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1550       return GL_FALSE;
1551
1552    return GL_TRUE;
1553 }
1554
1555
1556 /**
1557  * Do one-time initialization for the given framebuffer.  Specifically,
1558  * ask the driver for the window's current size and update the framebuffer
1559  * object to match.
1560  * Really, the device driver should totally take care of this.
1561  */
1562 static void
1563 initialize_framebuffer_size(GLcontext *ctx, GLframebuffer *fb)
1564 {
1565    GLuint width, height;
1566    if (ctx->Driver.GetBufferSize) {
1567       ctx->Driver.GetBufferSize(fb, &width, &height);
1568       if (ctx->Driver.ResizeBuffers)
1569          ctx->Driver.ResizeBuffers(ctx, fb, width, height);
1570       fb->Initialized = GL_TRUE;
1571    }
1572 }
1573
1574
1575 /**
1576  * Bind the given context to the given drawBuffer and readBuffer and
1577  * make it the current context for the calling thread.
1578  * We'll render into the drawBuffer and read pixels from the
1579  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1580  *
1581  * We check that the context's and framebuffer's visuals are compatible
1582  * and return immediately if they're not.
1583  *
1584  * \param newCtx  the new GL context. If NULL then there will be no current GL
1585  *                context.
1586  * \param drawBuffer  the drawing framebuffer
1587  * \param readBuffer  the reading framebuffer
1588  */
1589 void
1590 _mesa_make_current( GLcontext *newCtx, GLframebuffer *drawBuffer,
1591                     GLframebuffer *readBuffer )
1592 {
1593    if (MESA_VERBOSE & VERBOSE_API)
1594       _mesa_debug(newCtx, "_mesa_make_current()\n");
1595
1596    /* Check that the context's and framebuffer's visuals are compatible.
1597     */
1598    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1599       if (!check_compatible(newCtx, drawBuffer)) {
1600          _mesa_warning(newCtx,
1601               "MakeCurrent: incompatible visuals for context and drawbuffer");
1602          return;
1603       }
1604    }
1605    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1606       if (!check_compatible(newCtx, readBuffer)) {
1607          _mesa_warning(newCtx,
1608               "MakeCurrent: incompatible visuals for context and readbuffer");
1609          return;
1610       }
1611    }
1612
1613    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1614    _glapi_set_context((void *) newCtx);
1615    ASSERT(_mesa_get_current_context() == newCtx);
1616
1617    if (!newCtx) {
1618       _glapi_set_dispatch(NULL);  /* none current */
1619    }
1620    else {
1621       _glapi_set_dispatch(newCtx->CurrentDispatch);
1622
1623       if (drawBuffer && readBuffer) {
1624          /* TODO: check if newCtx and buffer's visual match??? */
1625
1626          ASSERT(drawBuffer->Name == 0);
1627          ASSERT(readBuffer->Name == 0);
1628          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1629          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1630
1631          /*
1632           * Only set the context's Draw/ReadBuffer fields if they're NULL
1633           * or not bound to a user-created FBO.
1634           */
1635          if (!newCtx->DrawBuffer || newCtx->DrawBuffer->Name == 0) {
1636             /* KW: merge conflict here, revisit.
1637              */
1638             /* fix up the fb fields - these will end up wrong otherwise
1639              * if the DRIdrawable changes, and everything relies on them.
1640              * This is a bit messy (same as needed in _mesa_BindFramebufferEXT)
1641              */
1642             unsigned int i;
1643             GLenum buffers[MAX_DRAW_BUFFERS];
1644
1645             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1646
1647             for(i = 0; i < newCtx->Const.MaxDrawBuffers; i++) {
1648                buffers[i] = newCtx->Color.DrawBuffer[i];
1649             }
1650
1651             _mesa_drawbuffers(newCtx, newCtx->Const.MaxDrawBuffers, buffers, NULL);
1652          }
1653          if (!newCtx->ReadBuffer || newCtx->ReadBuffer->Name == 0) {
1654             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1655          }
1656
1657          /* XXX only set this flag if we're really changing the draw/read
1658           * framebuffer bindings.
1659           */
1660          newCtx->NewState |= _NEW_BUFFERS;
1661
1662 #if 1
1663          /* We want to get rid of these lines: */
1664
1665 #if _HAVE_FULL_GL
1666          if (!drawBuffer->Initialized) {
1667             initialize_framebuffer_size(newCtx, drawBuffer);
1668          }
1669          if (readBuffer != drawBuffer && !readBuffer->Initialized) {
1670             initialize_framebuffer_size(newCtx, readBuffer);
1671          }
1672
1673          _mesa_resizebuffers(newCtx);
1674 #endif
1675
1676 #else
1677          /* We want the drawBuffer and readBuffer to be initialized by
1678           * the driver.
1679           * This generally means the Width and Height match the actual
1680           * window size and the renderbuffers (both hardware and software
1681           * based) are allocated to match.  The later can generally be
1682           * done with a call to _mesa_resize_framebuffer().
1683           *
1684           * It's theoretically possible for a buffer to have zero width
1685           * or height, but for now, assert check that the driver did what's
1686           * expected of it.
1687           */
1688          ASSERT(drawBuffer->Width > 0);
1689          ASSERT(drawBuffer->Height > 0);
1690 #endif
1691
1692          if (newCtx->FirstTimeCurrent) {
1693             /* set initial viewport and scissor size now */
1694             _mesa_set_viewport(newCtx, 0, 0,
1695                                drawBuffer->Width, drawBuffer->Height);
1696             _mesa_set_scissor(newCtx, 0, 0,
1697                               drawBuffer->Width, drawBuffer->Height );
1698             check_context_limits(newCtx);
1699          }
1700       }
1701
1702       /* We can use this to help debug user's problems.  Tell them to set
1703        * the MESA_INFO env variable before running their app.  Then the
1704        * first time each context is made current we'll print some useful
1705        * information.
1706        */
1707       if (newCtx->FirstTimeCurrent) {
1708          if (_mesa_getenv("MESA_INFO")) {
1709             _mesa_print_info();
1710          }
1711          newCtx->FirstTimeCurrent = GL_FALSE;
1712       }
1713    }
1714 }
1715
1716
1717 /**
1718  * Make context 'ctx' share the display lists, textures and programs
1719  * that are associated with 'ctxToShare'.
1720  * Any display lists, textures or programs associated with 'ctx' will
1721  * be deleted if nobody else is sharing them.
1722  */
1723 GLboolean
1724 _mesa_share_state(GLcontext *ctx, GLcontext *ctxToShare)
1725 {
1726    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1727       struct gl_shared_state *oldSharedState = ctx->Shared;
1728
1729       ctx->Shared = ctxToShare->Shared;
1730       ctx->Shared->RefCount++;
1731
1732       update_default_objects(ctx);
1733
1734       oldSharedState->RefCount--;
1735       if (oldSharedState->RefCount == 0) {
1736          free_shared_state(ctx, oldSharedState);
1737       }
1738
1739       return GL_TRUE;
1740    }
1741    else {
1742       return GL_FALSE;
1743    }
1744 }
1745
1746
1747
1748 /**
1749  * \return pointer to the current GL context for this thread.
1750  *
1751  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1752  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1753  * context.h.
1754  */
1755 GLcontext *
1756 _mesa_get_current_context( void )
1757 {
1758    return (GLcontext *) _glapi_get_context();
1759 }
1760
1761
1762 /**
1763  * Get context's current API dispatch table.
1764  *
1765  * It'll either be the immediate-mode execute dispatcher or the display list
1766  * compile dispatcher.
1767  *
1768  * \param ctx GL context.
1769  *
1770  * \return pointer to dispatch_table.
1771  *
1772  * Simply returns __GLcontextRec::CurrentDispatch.
1773  */
1774 struct _glapi_table *
1775 _mesa_get_dispatch(GLcontext *ctx)
1776 {
1777    return ctx->CurrentDispatch;
1778 }
1779
1780 /*@}*/
1781
1782
1783 /**********************************************************************/
1784 /** \name Miscellaneous functions                                     */
1785 /**********************************************************************/
1786 /*@{*/
1787
1788 /**
1789  * Record an error.
1790  *
1791  * \param ctx GL context.
1792  * \param error error code.
1793  *
1794  * Records the given error code and call the driver's dd_function_table::Error
1795  * function if defined.
1796  *
1797  * \sa
1798  * This is called via _mesa_error().
1799  */
1800 void
1801 _mesa_record_error(GLcontext *ctx, GLenum error)
1802 {
1803    if (!ctx)
1804       return;
1805
1806    if (ctx->ErrorValue == GL_NO_ERROR) {
1807       ctx->ErrorValue = error;
1808    }
1809
1810    /* Call device driver's error handler, if any.  This is used on the Mac. */
1811    if (ctx->Driver.Error) {
1812       ctx->Driver.Error(ctx);
1813    }
1814 }
1815
1816
1817 /**
1818  * Execute glFinish().
1819  *
1820  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1821  * dd_function_table::Finish driver callback, if not NULL.
1822  */
1823 void GLAPIENTRY
1824 _mesa_Finish(void)
1825 {
1826    GET_CURRENT_CONTEXT(ctx);
1827    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1828    if (ctx->Driver.Finish) {
1829       ctx->Driver.Finish(ctx);
1830    }
1831 }
1832
1833
1834 /**
1835  * Execute glFlush().
1836  *
1837  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1838  * dd_function_table::Flush driver callback, if not NULL.
1839  */
1840 void GLAPIENTRY
1841 _mesa_Flush(void)
1842 {
1843    GET_CURRENT_CONTEXT(ctx);
1844    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1845    if (ctx->Driver.Flush) {
1846       ctx->Driver.Flush(ctx);
1847    }
1848 }
1849
1850
1851 /*@}*/